1. Filed
The present invention relates to a light emitting diode assembly, and more particularly, to a light emitting diode assembly including a red light emitting diode chip.
2. Discussion of the Background
Light emitting diodes are used as light sources in various products. Particularly, light emitting diodes are used as light sources for backlight units, displays, lighting fixtures, and the like, and can emit white light through combination of light emitting diodes emitting various colors, or combination with phosphors. Particularly, white light can be realized through combination of a blue light emitting diode and a yellow phosphor. However, since the combination of the blue light emitting diode and the yellow phosphor provides white light showing a lack of red emission, a light emitting diode assembly based on this combination has relatively poor color rendering index and relatively high color temperature. Accordingly, a light emitting diode assembly designed to emit white light through combination of light emitting diodes and phosphors also employs a red light emitting diode in order to improve the color rendering index and the color temperature.
As compared with AlInGaN-based blue or UV light emitting diodes, AlInGaP-based red light emitting diodes emit relatively large amounts of heat. Moreover, the red light emitting diodes exhibit significant spectrum shifts according to change of temperature.
As a result, in a light emitting diode assembly including a red light emitting diode, spectrum shift of red light occurs as the junction temperature of the red light emitting diode increases. Thus, even in the case where the light emitting diode assembly realizes white light in desired color coordinates in initial operation, the color coordinates change over time, making it difficult to realize desired white light.